Lost?

479 Views 15 Replies 7 Participants Last post by Tomvw, 2 mo ago

Jhush312

Discussion Starter · 3 mo ago

I'm at a point that I can't get this figured out. But I also don't have a vag/com to hook up either. These are the things I have done to the car.
1. Plugs/wires
2, fuel filter
3. New injectors
4. Aftermarket cold air intake
5. Cam sensor & crankshaft sensor
6. Cleaned maf, and throttle body
7. Timing belt/ with water pump and pulleys
I've done all this work and still have power loss somehow at low rpm til I 3000 and it seems like it runs like it should

1 - 16 of 16 Posts

VAGguy

· #2 · 3 mo ago

That's a lot of money spent without diagnosis. You can even use some third party phone apps to pull codes and look at sensors for a small subscription fee.

You left out the details of the car. Assuming it's a 1998-2005 V6, but please share more like mileage, major repair history and other symptoms, if any.

Reactions: 1

ylwagon

· #3 · 3 mo ago

Jhush312 said:
4. Aftermarket cold air intake

What was the point of doing that? Is it the kind that you oil?

Reactions: 2

AndreasPassat

· #4 · 3 mo ago

That's a lot of coin to throw at a problem.
New injectors? Very rarely are new injectors ever needed unless you are going forced induction.
Was the power loss always there? Have you done a compression test? On the face of things, it seems as though the timing is off.

Reactions: 2

Jhush312

Discussion Starter · #5 · 3 mo ago

It's a 99 2.8l v6. When I bought the car it was a repo. The clutch was out of it so that was the first thing I replaced. It had 120k on it when I got it. The power loss has always been there since I've owned it. Even after I replaced the timing belt it seems the same as it was before. The only codes that have shown when I've scanned it before were the o2 sensors upstream, due to no catalytic converters. And also the tps sensor. Now the car just rolled a 140k on it. I've never done a compression test on it before so idk about that.

Timberto

· #6 · 3 mo ago

I diagnosed a bad injector once, on one of the several dozens of dozens of VW in my fleet over time, and when I went to install the new one the connector was just hanging there, not plugged in. Do what you think is best, but like Andreas above injectors have never been a fail point for me.

VAGguy

· #7 · 3 mo ago

Jhush312 said:
It's a 99 2.8l v6. When I bought the car it was a repo. The clutch was out of it so that was the first thing I replaced. It had 120k on it when I got it. The power loss has always been there since I've owned it. Even after I replaced the timing belt it seems the same as it was before. The only codes that have shown when I've scanned it before were the o2 sensors upstream, due to no catalytic converters. And also the tps sensor. Now the car just rolled a 140k on it. I've never done a compression test on it before so idk about that.

Woah, so does it have working O2 sensors and cats now? The ECU can't do it's job with power delivery without the sensors and a working cat.

Reactions: 1

AndreasPassat

· #8 · 3 mo ago

What VAGguy said ^^

Jhush312

Discussion Starter · #9 · 3 mo ago

It doesn't have cats just the o2 sensors

Tomvw

· #10 · 3 mo ago

You won't get it to run properly if the upstream O2 sensors (Bank 1/S1 & Bank 2/S1) are not working properly.
The downstream O2 sensors (S2) will not work without the cats, but they won't affect performance.

Reactions: 2

Jhush312

Discussion Starter · #11 · 3 mo ago

Yeah but still wouldn't effect Power loss I'm having

geronimomo

· #12 · 3 mo ago

How about the drive unit? 078133619?

Jhush312

Discussion Starter · #13 · 3 mo ago

I'm not sure what you mean by that ? It's a 2.8l v6 with a 5 speed manua

VAGguy

· #14 · 3 mo ago

Jhush312 said:
I'm not sure what you mean by that ? It's a 2.8l v6 with a 5 speed manua

https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/intake-manifold-actuator/078133619b/

Jhush312

Discussion Starter · #15 · 3 mo ago

I have not tried that but I did replace all the vacuum lines

Tomvw

· #16 · 2 mo ago

Jhush312 said:
Yeah but still wouldn't effect Power loss I'm having

Upstream O2 sensors not working properly, will cause power loss.

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